A5019872303- Particle physics theoretical and experimental studies
- Neutrino Physics Research
- Dark Matter and Cosmic Phenomena
- Black Holes and Theoretical Physics
- Cosmology and Gravitation Theories
- Quantum Chromodynamics and Particle Interactions
- Astrophysics and Cosmic Phenomena
- Noncommutative and Quantum Gravity Theories
- Algebraic structures and combinatorial models
- Advanced Topics in Algebra
- Quantum Mechanics and Non-Hermitian Physics
- High-Energy Particle Collisions Research
- Atomic and Subatomic Physics Research
- Nonlinear Waves and Solitons
- Particle Detector Development and Performance
- Computational Physics and Python Applications
- Algebraic and Geometric Analysis
- Pulsars and Gravitational Waves Research
- Quantum Mechanics and Applications
- Galaxies: Formation, Evolution, Phenomena
- Quantum chaos and dynamical systems
- International Science and Diplomacy
- Relativity and Gravitational Theory
- Quantum, superfluid, helium dynamics
- Gamma-ray bursts and supernovae
University of Maryland, College Park
2016-2025
University of Tennessee at Knoxville
2015
Ispat General Hospital
2015
Technical University of Munich
2005-2007
University of Regina
2004
Fermi National Accelerator Laboratory
1987-2003
The University of Texas at Austin
1998
University of Oregon
1998
U.S. National Science Foundation
1980-1997
The Abdus Salam International Centre for Theoretical Physics (ICTP)
1996
In weak-interaction models with spontaneous parity nonconservation, based on the gauge group $\mathrm{SU}{(2)}_{L}\ensuremath{\bigotimes}\mathrm{SU}{(2)}_{R}\ensuremath{\bigotimes}\mathrm{U}(1)$, we obtain following formula for neutrino mass: ${m}_{{\ensuremath{\nu}}_{e}}\ensuremath{\simeq}\frac{{{m}_{e}}^{2}}{g{m}_{{W}_{R}}}$, where ${W}_{R}$ is boson which mediates right-handed weak interactions. This formula, valid each lepton generation, relates maximality of observed nonconservation at...
Unified electroweak gauge theories based on the group $\mathrm{SU}{(2)}_{L}\ifmmode\times\else\texttimes\fi{}\mathrm{SU}{(2)}_{R}\ifmmode\times\else\texttimes\fi{}\mathrm{U}{(1)}_{B\ensuremath{-}L}$, in which breakdown of parity invariance is spontaneous, lead most naturally to a massive neutrino. Assuming neutrino be Majorana particle, we show that smallness its mass can understood as result observed maximality violation low-energy weak interactions. This shown independent number...
It is remarked that left-right symmetry of the starting gauge interactions a "natural" if it broken in no way except possibly by mass terms Lagrangian. The implications this result for unification coupling constants and parity nonconservation at low high energies are stressed.
Left-right symmetry in the starting gauge interactions provides basis for an "isoconjugate" model of $\mathrm{CP}$ violation with consequence that ${\ensuremath{\eta}}_{+\ensuremath{-}}={\ensuremath{\eta}}_{00}$. The magnitude is naturally suppressed at least to extent $V+A$ are nature compared $V\ensuremath{-}A$ interactions. This allows possibility intrinsic $\mathrm{CP}$-violating phase (arising through spontaneous breaking, example) may have a maximal character, which reveal itself...
We propose new mechanisms for understanding neutrino masses in superstring models that contain ${\mathrm{E}}_{6}$-singlet zero-mass fields after compactification. show the low-energy gauge group of these can be phenomenologically acceptable. then comment on \ensuremath{\Delta}B=1 and \ensuremath{\Delta}B=2 baryon-number-violating processes models.
We propose a new mechanism for understanding small neutrino masses in supersymmetric theories without unnatural fine tuning of parameters. This idea may be useful superstring ${\mathrm{E}}_{6}$ models, where the conventional is not available suppressing masses.
This paper describes the physics case for a new fixed target facility at CERN SPS. The SHiP (Search Hidden Particles) experiment is intended to hunt in largely unexplored domain of very weakly interacting particles with masses below Fermi scale, inaccessible LHC experiments, and study tau neutrino physics. same proton beam setup can be used later look decays tau-leptons lepton flavour number non-conservation, $\tau\to 3\mu$ search weakly-interacting sub-GeV dark matter candidates. We discuss...
In supersymmetric theories with R-parity violation, there are new contributions to neutrinoless double-beta [(\ensuremath{\beta}\ensuremath{\beta}${)}_{0\ensuremath{\nu}}$] decay that do not involve the exchange of Majorana neutrinos. Experimental information on (\ensuremath{\beta}\ensuremath{\beta}${)}_{0\ensuremath{\nu}}$ can therefore be used constrain parameters theories. We also discuss neutrino mass in these then how R-parity-violating interactions induced low-energy sector a theory...
We examine the theoretical motivations for long-lived particle (LLP) signals at LHC in a comprehensive survey of Standard Model (SM) extensions. LLPs are common prediction wide range theories that address unsolved fundamental mysteries such as naturalness, dark matter, baryogenesis and neutrino masses, represent natural generic possibility physics beyond SM (BSM). In most cases LLP lifetime can be treated free parameter from $\mu$m scale up to Big Bang Nucleosynthesis limit $\sim 10^7$m....
A new approach to left-right symmetric models is proposed, where the discrete-symmetry- and $\mathrm{SU}{(2)}_{R}$-breaking scales are decoupled from each other. This changes spectrum of physical Higgs bosons which leads different patterns for gauge hierarchies in $\mathrm{SU}{(2)}_{L}\ensuremath{\bigotimes} \mathrm{SU}{(2)}_{R}\ensuremath{\bigotimes} \mathrm{SU}{(4)}_{C}$ SO(10) models. Most interesting two symmetry-breaking chains with an intermediate $\mathrm{U}{(1)}_{R}$ symmetry. These...
We suggest that recent neutrino puzzles are the solar and atmospheric deficits as well possible oscillations reported by LSND experiment possibility of massive neutrinos providing hot component cosmological dark matter, can all be naturally explained assuming existence a mirror world described an ``electroweak'' gauge symmetry $[SU(2)\times U(1)]'$, with breaking scale larger about factor 30 than standard $SU(2)\times U(1)$ model. An interesting aspect this model is sterile arise from hidden...
If the solar and atmospheric neutrino deficits apparent need for a hot dark matter component all result from mass, one of three mass patterns is required. Of these, two appear quite unlikely, leading to unique solution which points further experimental tests. We briefly outline possible theoretical models could generate these matrices without adjustment parameters.
We show that the bimaximal neutrino mixing pattern suggested by solar and atmospheric data can be derived from maximal, symmetric, four-neutrino in limit one of neutrinos is made heavy. Imposing constraints no neutrinoless double beta decay a 20% hot dark matter component universe leads to three-neutrino mass matrix recently Georgi Glashow. Our result useful constructing theoretical models for pattern. illustrate this simple example.
We consider the possible emission of right-handed neutrinos ${v}_{R}$ from SN1987A by neutrinomagnetic-moment interactions. By imposing a bound on luminosity, we get limit neutrino magnetic moment, ${\ensuremath{\mu}}_{v}<(0.2\ensuremath{-}0.8)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}{\ensuremath{\mu}}_{B}$, depending core temperature. It appears that consideration number high-energy ($E\ensuremath{\simeq}100\ensuremath{-}200$ MeV) events should have been observed in...
We present a solution to the strong $\mathrm{CP}$ problem using softly broken parity invariance in context of left-right-symmetric gauge models with "seesaw" mechanism for quark masses. A distinguishing feature model is that first nonvanishing contribution $\overline{\ensuremath{\theta}}$ arises only at two-loop level, whereas electric dipole moment neutron ${d}_{n}^{e}$ generated one-loop level via weak violation. For ${W}_{R}$ mass TeV scale, we estimate...
We propose a new approach to the left-right-symmetric models of weak interactions where parity-and ${\mathrm{SU}(2)}_{R}$-breaking scales are decoupled from each other. This changes spectrum Higgs bosons, which in turn affects evolution various gauge coupling constants with energy. has profound implications for mass hierarchies partial unification based on ${\mathrm{SU}(2)}_{L}\ifmmode\times\else\texttimes\fi{}{\mathrm{SU}(2)}_{R}\ifmmode\times\else\texttimes\fi{}{\mathrm{SU}(4)}_{C}$ and...